<html>
<head>
<title>Subframe form</title>
<script>
// Simulate the user clicking on the submit button.
function submitForm(name) {
  var form = document.getElementById("form");
  var node = form.contentDocument.getElementById(name);
  node.click();
  return true;
}
</script>
</head>
<body>
<iframe src="form.html" id="form" name="form"></iframe>
</body>
</html>
